Butterfly valve

ABSTRACT

A butterfly valve includes a body, a gear assembly, a shaft, a Scotch yoke actuator on the shaft, and a gear box cover. The body has a fluid conduit and a gear platform supported on and over the fluid conduit. The shaft passes through the gear platform. The gear assembly is supported on the gear platform and includes a valve stem with a first threaded portion and includes a pin nut with a second threaded portion engaging the first threaded portion. The Scotch yoke actuator engages the pin nut. The gear box cover defines an internal cavity sized to house the gear assembly.

REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of co-pending U.S. patentapplication Ser. No. 17/144,419, filed Jan. 8, 2021, entitled “ButterflyValve”. U.S. patent application Ser. No. 17/144,419 is incorporatedherein by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The invention pertains to the field of valves. More particularly, theinvention pertains to butterfly valves.

Description of Related Art

A butterfly valve regulates the flow of fluid. The valve has a body witha passage, through which fluid can be allowed to flow, or through whichfluid flow can be blocked by a closing mechanism. The closing mechanismis a disk in the passage that rotates from an open position parallelwith an axis of the valve body to a closed position perpendicular withthe axis of the valve body. A gearbox attached to the valve body encasesinternal components that facilitate rotation of the disk between theopen position and the closed position. In conventional butterfly valves,the gearbox has four sides integral with a base, and top plate toenclose the remaining side. The base and four sides of the gear box,being integral with the body of the valve, are formed from a materialsuch as iron or steel, which are more substantial than, for example,aluminum. To meet certain industry standards, the body of the valve mustbe made from a more substantial material like iron or steel in order tobetter keep the valve open in the case of a fire. The components insidethe gear box can be accessed for maintenance by removing the top plate.Access to the internal components through the space occupied by the topplate is restricted by the four sides integral with the base.

SUMMARY OF THE INVENTION

A butterfly valve disclosed herein has improved accessibility to thecomponents inside the gear box, lowered weight, decreased manufacturingcost, and increased manufacturing ease.

In one embodiment, a butterfly valve includes: a body having a fluidconduit and a gear platform supported on and over the fluid conduit, thegear platform configured to support a gear assembly for actuating avalve disk between an open position and a closed position; and a gearbox cover defining an internal cavity, the internal cavity sized tohouse the gear assembly, the gear box cover configured to be removablymounted to the platform such that the internal cavity is between thegear box cover and the platform.

In another embodiment, a butterfly valve includes: a body having a firstopening, a second opening, a third opening, and a passage extendingbetween the first opening and the second opening, the passage having afirst axis, the third opening having a second axis transverse to thepassage; a disk within the passage, the disk having an open positionwherein the disk is non-perpendicular to the axis of the body and aclosed position wherein the disk is perpendicular to the axis of thebody; a platform supported on the body, the platform having a firstopening aligned with the third opening of the body; a gear assemblysupported on the platform; a shaft coupled to the disk, the shaftpassing through the third opening of the body and the first opening ofthe platform; and a gear box cover having a plurality of sides definingan internal cavity, the internal cavity sized to house the gearassembly, the gear box cover configured to be removably mounted to andcovering the platform.

In another embodiment a butterfly valve includes: a body having a firstportion, a second portion, and a passage with an axis, a first bearingcase extending from the first portion of the body, the first bearingcase having an opening therethrough to pass a shaft; a second bearingcase on the second portion of the body, the second bearing case alignedwith the opening of the first bearing case; a platform supported overthe first portion of the body, the platform having an opening to pass ashaft, the opening of the platform aligned with the opening of the firstbearing case; a valve stem supported on the platform by a support, thevalve stem having a threaded portion; a pin nut having a pin and athreaded portion engaging the threaded portion of the valve stem; a diskwithin the passage of the body, the disk having an open position whereinthe disk is non-perpendicular to the axis of the passage and a closedposition wherein the disk is perpendicular to the axis of the passage; afirst shaft including a first end coupled to the disk, a second endopposite the first end, and a length between the first end of the firstshaft and the second end of the first shaft, the length passing throughthe opening of the first bearing case and the opening of the platform; aScotch yoke actuator on the length between the platform and the secondend of the first shaft, the Scotch yoke having a slot fitting the pin onthe pin nut; a second shaft having a first end coupled to the disk, asecond end in the second bearing case, and a length between the firstend of the second shaft and the second end of the second shaft; and agear box cover removably mounted to and covering the platform, the gearbox cover having a first opening to pass the first shaft, the gear boxcover having a second opening to pass the valve stem.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows an exploded view of the butterfly valve, according to anembodiment.

FIG. 2 shows a partially exploded view of a butterfly valve, accordingto an embodiment.

FIG. 3 shows an end view of the butterfly valve of FIG. 1 .

FIG. 4 shows a side view of the butterfly valve of FIG. 1 .

FIG. 5 shows a bottom view of the butterfly valve of FIG. 1 .

FIG. 6 shows a transparent top view of a limit switch in aclosed-circuit position, according to the embodiment of the butterflyvalve of FIG. 2 .

FIG. 7 shows a transparent top view of the limit switch of FIG. 6 in anopen-circuit position.

FIG. 8 shows disassembly of a gear box cover from a butterfly valve,according to the embodiment of FIG. 2 .

DETAILED DESCRIPTION OF THE INVENTION

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. As usedherein, the singular forms “a”, “an”, and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises,” “comprising,” “including,” and“having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

When an element or layer is referred to as being “on”, “engaged to”,“connected to” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present. In contrast,when an element is referred to as being “directly on,” “directly engagedto”, “directly connected to” or “directly coupled to” another element orlayer, there may be no intervening elements or layers present. Otherwords used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.). As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items.

Spatially relative terms, such as “inner,” “outer,” “beneath”, “below”,“lower”, “above”, “upper” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Spatiallyrelative terms may be intended to encompass different orientations ofthe device in use or operation in addition to the orientation depictedin the figures. For example, if the device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

FIG. 1 shows an exploded view of a butterfly valve 100. FIG. 2 shows apartially exploded view of a second butterfly valve 200. FIG. 3 shows aside view of the valve 100. FIG. 4 shows a view of the valve 100 fromthe right-hand side of FIG. 1 . FIG. 5 shows a view of the valve 100from the bottom of valve 100. Identical reference numbers are used inall of the figures to refer to the same elements of the valve 100, 200.

Referring to FIGS. 1-5 , the valve 100, 200 has a body 1 with a base orplatform 21 supported on the body 1 by supports 23. The body 1, thesupports 23, and the platform 21 can be formed, e.g., cast, as oneintegral unit. The body 1, including the supports 23 and the platform 21can be formed of iron. Other materials with suitably strong and fireresistant characteristics can alternatively be used. A central passage26 leads through a fluid conduit 49 of the valve body 1. The fluidconduit 49 has fittings on either end of the passage to permit the valve100, 200 to be fitted into a pipe or other fluid conduit. These fittingsare shown in the drawing as flanges 32 having an inner diameter 27,which is larger than the diameter 28 of the passage 26, although it willbe understood that other fittings can be used as needed by the valveapplication.

The body 1 has an upper bearing case 25 formed on an upper surface orportion 34 of the body 1, a lower bearing case 33 formed on a lowersurface or portion 35 of the body 1, and a platform bearing case 24formed on the platform 21.

A circular disk 2 fits within the passage 26. When the disk 2 is in afully open position wherein the disk 1 is parallel to an axis 36 of thevalve body, fluid can flow through the passage 26 in the body 1 nearlyunobstructed. When the disk 2 is rotated to a closed position whereinthe disk 2 is perpendicular to the axis 36 of the valve body 1, the disk2 blocks fluid flow through the passage 26. Intermediate positions ofthe disk 2 can be used to control flow through the passage 26 betweenfull flow and no flow, as is well known in the art.

The disk 2 is supported and rotated by a lower shaft 5 and an uppershaft 6, which are each fastened to the disk 2 on a rotational axis 37of the disk. This fastening can be accomplished by screwing threadedends of lower shaft 5 and upper shaft 6 into mating sockets on the disk2, or by other means known to the art. The lower shaft 5 is supportedwithin the body 1 by lower bearing 4 fitting within lower bearing case33, and the upper shaft 6 is supported within the body 1 by upperbearing 3 fitting within upper bearing case 25. O-rings 18 can beprovided on either side of the upper bearing 3 to minimize fluid leakagearound the bearing 3. The upper shaft 6 passes through the platform 21through the platform bearing case 24. The upper bearing case 25 and body1 have an opening 38, and the platform bearing case 24 and platform 21have an opening 39, the openings 38, 39 aligned and sized to fit aroundthe upper shaft 6. The lower bearing case 33 may have a central opening40 extending also through the lower portion 35 of the body 1 to permitthe lower shaft 5 to extend outside of the body 1 as shown in thedrawing.

The platform 21 supports components of a gear assembly, a valve positionindicator assembly, and a removable gear box cover or hood 19. As partof the gear assembly, the valve stem 8 is mounted with bushes 9, 11 andlock nut 12 to the platform 21 by a flange or support 22. The valve stem8 has a threaded portion 31, which mates with a threaded portion 29 of apin nut 7, so that rotation of the valve stem 8 causes linear movementof the pin nut 7 along an axis of the valve stem 8. The valve stem 8 canbe rotated automatically, or as illustrated in FIG. 2 , manually, suchas by rotating a handwheel 42 attached to an end 43 of the valve stem 8.The handwheel 42 can be fastened to the valve stem 8 using conventionalmethods, such as with a screw through the handwheel into screw hole 55.

A Scotch yoke actuator arm 30 is mounted on the upper shaft 6 at aposition above the threaded portion 31 of the stem 8, in someembodiments by casting the Scotch yoke actuator arm 30 with the uppershaft 6. Pin nut 7 has a pin 40 which fits within a slot 41 in theScotch yoke actuator 30, so that as the valve stem 8 rotates and the pinnut 7 moves linearly, the Scotch yoke actuator arm 30 rotates. As aresult, the disk 2 also rotates.

As part of the valve position indicator assembly, rotation of the Scotchyoke actuator arm 30 also operates at least one limit switch 14 forremote indication of the position of the disk 2. FIG. 6 shows atransparent top view of the limit switch 14 in a closed-circuitposition, and FIG. 7 shows a transparent top view of the limit switch 14in an open-circuit position. The pin nut 7 and limit switch 14 can bearranged such that the limit switch 14 is actuated when the valve disk 2is at either the open position or the closed position, or while thevalve disk 2 is between the open and closed positions. Alternatively,separate limit switches 14 can be provided to be operated by the pin nut7 at each of the open and closed positions. If desired, a flag orindicator 13 can be mounted on the top end of the upper shaft 6 tovisually signal the position of the disk 2 to an operator. The uppershaft 6 can extend through an opening 44 in a top side 45 of the gearbox cover 19.

Referring again to FIGS. 1-5 and also to FIG. 8 , which illustratesremoval of the gear box cover 19, the removable gear box cover 19 cancover the threaded portion 31 of the stem 8, the Scotch yoke actuator30, the pin nut 7, the limit switch 14, and any other components mountedon or above the platform 21. The gear box cover 19 has a plurality ofsides, including the top side 45 and four perimeter sides 46, whichtogether define an internal cavity 47. The gear box cover 19 can beshaped alternatively, such that the top side 45 and four perimeter sides46 can be considered a different number of sides, or a one or morerounded or curved sides, to create the internal cavity 47. The internalcavity 47 is sized to house components of the gear assembly and thevalve position indicator assembly. The gear box cover 19 can relativelyeasily be fastened and unfastened from the platform 21, such as bytightening or loosening fasteners 54 (e.g., screws) shown in FIG. 2 .After unfastening the fasteners, as shown in FIG. 8 , the gear box cover19 can be tilted at one end. If the handwheel 42 is removed, the gearbox cove 19 can further be slid off the valve stem 8. Because the gearbox cover 19 is detachable from the platform 21 and body 1 rather thanintegral with the platform 21 and body 1, the gear box 19 can beclassified as a switch cover and the gear box 19 can allow the butterflyvalve 100, 200 to meet the necessary industry standards, including fireratings, while more easily and inexpensively being fabricated from amachinable, lighter material, such as aluminum. Removal of the gear boxcover 19 also permits much easier access to the components within theinternal cavity 47, as opposed to conventional removal of just the topside 45.

As shown in FIG. 1 , one of the perimeter sides 46 has a side opening48, which can be covered by a side plate 10. The side plate 10 has afurther opening sized to fit and mount bushing 9. The side plate 10closes the side opening 48 around the stem 8 or bushing 9. Gasket 20 ando-rings 15, 16, 17 provide a seal against dirt and moisture entry intothe gear box cover 19. While the gear box cover 19 is removable so thatcomponents under the gear box cover 19 are easily accessible, the sideopening 48 and the side plate 10 also provide access without removal ofthe entire gear box cover 19.

FIG. 2 shows an alternate side opening 248, which is sized smaller thanthe side opening 48, to fit the stem 8 and a gasket 220. The gasketseals between the valve stem 8 and one of the perimeter side 46. FIG. 2also shows an opening 202 and a conduit connector 204 to allowentry/exit of an electrical supply 201 or other communication path, topower and/or communicate with the limit switch 14.

Accordingly, it is to be understood that the embodiments of theinvention herein described are merely illustrative of the application ofthe principles of the invention. Reference herein to details of theillustrated embodiments is not intended to limit the scope of theclaims, which themselves recite those features regarded as essential tothe invention.

What is claimed is:
 1. A butterfly valve comprising: a body having afluid conduit and a gear platform, the gear platform supported on andover the fluid conduit, the gear platform being formed integrally withthe body; a gear assembly to actuate a valve disk between an openposition and a closed position, the gear assembly directly mounted tothe gear platform, the gear assembly including: a valve stem having afirst threaded portion; and a pin nut having a second threaded portionengaging the first threaded portion; a shaft passing through the gearplatform; a Scotch yoke actuator on the shaft, the Scotch yoke actuatorengaging the pin nut; and a gear box cover defining an internal cavity,the internal cavity sized to house the gear assembly, the gear box coverconfigured to be removably mounted to the gear platform separate fromthe gear assembly.
 2. The butterfly valve of claim 1, wherein the bodyis made of iron and the gear box cover is made of aluminum.
 3. Abutterfly valve comprising: a body having a fluid conduit and a gearplatform, the gear platform supported on and over the fluid conduit, thegear platform formed integrally with the body; a gear assemblyconfigured to actuate a valve disk between an open position and a closedposition, the gear assembly directly mounted to the gear platform, thegear assembly including: a valve stem supported on the gear platform,the valve stem having a first threaded portion; and a pin nut having asecond threaded portion engaging the first threaded portion; a shaftpassing through the gear platform; a Scotch yoke actuator on the shaft,the Scotch yoke actuator engaging the pin nut; and a gear box coverdefining an internal cavity, the internal cavity sized to house the gearassembly, the gear box cover configured to be mounted and unmounted fromthe gear platform while leaving the gear assembly supported on the gearplatform.
 4. A butterfly valve comprising: a body having a fluid conduitand a gear platform, the gear platform supported on and over the fluidconduit, the gear platform formed integrally with the body; a gearassembly configured to actuate a valve disk between an open position anda closed position, the gear assembly directly mounted to the gearplatform, the gear assembly including: a valve stem supported on thegear platform, the valve stem having a first threaded portion; and a pinnut having a second threaded portion engaging the first threadedportion; a shaft passing through the gear platform; a Scotch yokeactuator on the shaft, the Scotch yoke actuator engaging the pin nut;and a gear box cover defining an internal cavity, the internal cavitysized to house the gear assembly, the gear box cover having an open sideconfigured to receive the gear assembly into the internal cavity, theopen side of the gear box cover configured to be removably mounted tothe gear platform to enclose the gear assembly in the internal cavity.